If you receive a bounce message with this error, it's because an email recipient has directly complained about email originating from your IP address or account. In keeping with email sender best practices, MailChannels automatically blocks senders who receive complaints.
We unfortunately cannot reveal who complained about your email. To do so would enable spammers to fine tune or "wash" their recipient lists to avoid future detection. Complaints originate from email users on popular email services, including:
- Microsoft® Live Hotmail
- AOL Mail
- ... and others
What caused the error?
If you receive this type of rejection from us, it's possible you did nothing wrong. Email recipients frequently complain about legitimate messages. Sometimes it may seem easier to hit the "spam" button than the "delete" button. However, there are some things you can do to improve your chances of staying on the good side of your recipients, including:
- Only sending email messages that recipients could reasonably expect to receive;
- Not surprising recipients with new messages after many months of zero contact;
- Keeping the purpose of your communication as clear as possible; and,
- Providing unsubscribe links prominently at the top AND bottom of each message.
The M3AAWG Sender Best Common Practices document is an excellent resource and gives an overview of the current best common practices for sending commercial electronic messaging,
How long will I be blocked?
Our system uses an adaptive approach for blocking senders that receive complaints. Once the level of complaints drops back to an acceptable level, the sender will no longer be blocked. Unfortunately we do not generally accept requests to expedite the unblocking of a sender who has been blocked due to complaints.